Tongue Thickness and Its Clinical Significance

Abstract

Background: The tongue occupies most of the space in the oral cavity and it plays an important role in oral functions such as mastication, swallowing and articulation. The tongue continues to move from the time of intake to swallowing, particularly during masticating. A method for evaluating tongue thickness at rest by ultrasonography has been proposed; however, the association between tongue thickness and various oral functions remains unclear.
Objective: The purpose of this study was to investigate the relation between tongue thickness and oral functions, and to clarify the clinical significance of tongue thickness measurements in oral function maintenance.
Materials and Methods: Elderly outpatients were serially screened for enrollment and a total of 106 subjects (men, 54; women, 52; mean age, 75.2 ± 6.5 years) were selected. Age, body mass index, and functional teeth number including implant and pontic of fixed partial denture number were recorded as the basic attributes. Tongue thickness, tongue pressure, tongue thrust pressure and tongue motor function were measured as tongue assessments. Cheek pressure, oral moisture and occlusal force were measured as other oral functions.
Results: Subjects with thick tongue tended to have higher BMI, stronger muscle strengths and lower diadochokinesis. Diadochokinesis of /ka/, cheek pressure and functional teeth number were extracted as the independent factors affecting tongue thickness.
Conclusion: Tongue thickness does not necessarily reflect oral functions in healthy elderly people except for a negative association between tongue thickness and oral diadochokinesis of /ka/. Multiple assessments of tongue would be required to evaluate oral function, and the assessment of tongue thickness might have a different clinical meaning.